WO2023214916A1

WO2023214916A1 - A method and a device for ionization of a fluid

Info

Publication number: WO2023214916A1
Application number: PCT/SE2023/050415
Authority: WO
Inventors: Behzad FARZINPOUR
Original assignee: Brairtech Sweden Ab
Priority date: 2022-05-02
Filing date: 2023-05-02
Publication date: 2023-11-09

Abstract

The invention relates to a method for ionization of a fluid, wherein a first pair (18) of electrodes (20, 22) are arranged in a container (4, 404) opposite each other and at a distance from each other, wherein the method comprises the step of charging each one of the electrodes (20, 22) in the first pair (18) of electrodes so that they are simultaneously negatively or positively charged creating such a potential difference between each one of the electrodes (20, 22) and an environment of the respective electrode that electric discharges takes place from each one of the electrodes, wherein the method comprises the step of conveying the fluid in a gaseous state inside the container past the first pair (18) of electrodes in the environment of the respective electrode (20, 22) during said charging for ionization of the fluid.

Description

A method and a device for ionization of a fluid

TECHNICAL FIELD

The invention relates to a method and a device for ionization of a fluid in a gaseous state.

Ionization is a process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecule is called an ion.

The technical field of the invention regards ionization of the fluid by subjecting the fluid to an electric arc.

The fluid in gaseous state used as input to the ionization method may be air. When the electric arc is sufficiently strong, conditions are created for the gas to become separated into positive ions and electrons, wherein the air is ionized.

One area of application of an ionized gas is to clean a fluid, such as a gas, that may be air, or a liquid such as industrial process liquids and all kinds of water and wastewater and other liquids The ionized gas may be used for eliminating organic and mineral impurities or pollutants. Such organic matter may be bacteria, viruses, other harmful microorganisms, and some organic chemical substances. Also, for separation by sedimentation of the inorganic or mineral substances such as metal.

The disclosure in this chapter should not be regarded as any admittance of prior art.

PRIOR ART

WO2018/211309 discloses an electric arc ionization reactor and a method for generating ozone by using air. The reactor is elongated and has an inner circular cross section shape. An inlet for entry of air is provided at a first end of the elongated reactor and an outlet is provided at a second end of the elongated reactor. A pair of needle electrodes are arranged opposite each other and at a distance from each other in a transverse direction of the elongated reactor. An alternating current with high voltage is supplied to the electrodes for generating an arc between the electrodes. Buntat, Zokafle; Ozone generation using electrical discharges; A comparative study between Pulsed Streamer Discharge and Atmospheric Pressure Glow Discharge (2005). This thesis deals with an investigation into atmospheric pressure glow discharge and pulsed streamer discharge techniques of ozone generation, in an attempt to compare their performances in the generation of a high concentration and high yield of ozone. The art includes the comparison of the different methods of utilization of the corona discharge in atmospheric pressure by use of dielectric plates with the distance of maximum 1 mm form each other.

US20020170817 discloses the generating of a corona or other electric discharge and provides for the passing of a gas through the corona to effect ionizing, creating of ozone or the like. According to various methods of the invention, a corona discharge (or other electric discharge) is created, a gas is passed through the corona discharge; mixing of the gas may be provided by motionless mixing technique for one or more purposes, such as to assure maximum exposure of the gas to the corona discharge, to provide uniform temperature of the gas, to cool the corona generator, etc.

JP0761801 discloses an ozonizing unit providing a high ozone concentration by connecting a high-frequency power source across prescribed electrodes, carrying out the corona discharge and regulating the electric current while making the produced ozone gas flow in a spiral form and preventing ozone from being destroyed.

US4960569A discloses corona discharge ozonator is provided that comprises a first electrode, a second electrode and a dielectric material disposed between the electrodes. An ozonization chamber is formed between one of the electrodes and the dielectric material and defines a fluid flow path. A plurality of thermally-conducting solids are within the fluid flow path.

US6451208 discloses a device for applying electrostatic and magnetic fields to a fluid includes an outer conduit and an inner conduit forming a fluid passageway therebetween. The inner conduit is connected to a DC power source and the outer conduit along with electrode needles in electrical communication therewith are connected to ground. A baffle is positioned within the passageway to impart a spiral motion to the fluid flowing therein. SUMMARY

A first object of the invention is to achieve a method for ionizing a fluid flow, which creates conditions for a high ionization efficiency.

The object is achieved by a method according to claim 1 . Thus, it is achieved by a method for ionization of a fluid, wherein a first pair of electrodes are arranged in a container opposite each other and at a distance from each other, wherein the method comprises the step of charging each one of the electrodes in the first pair of electrodes so that they are simultaneously negatively or positively charged creating such a potential difference between each one of the electrodes and an environment of the respective electrode that electric discharges takes place from each one of the electrodes, wherein the method comprises the step of conveying the fluid in a gaseous state inside the container past the first pair of electrodes in the environment of the respective electrode during said charging for ionization of the fluid.

More specifically, both electrodes exchange electrons/positrons with the environment of the respective electrode eventually leading to a discharge and creation of independent semi arc structures in the vicinity of the respective electrode, in interaction with the conveyed fluid. The term “semi” here meaning that the arcs extend from the respective electrode a distance into the container, but there are no continuous arcs extending between the electrodes in the first pair.

The method creates conditions for creating electric discharges forming a configuration of a first independent semi arc structures athat are especially effective in ionization of the fluid. It may be achieved by supplying a voltage of a certain magnitude to the first pair of electrodes so that both electrodes simultaneously are of the same charge at each moment and providing the fluid in a fluid flow rate matching the magnitude of the voltage. More specifically, the method creates conditions for creating a configuration of the first independent semi arc structure downstream of the electrodes that covers a cross section of the container to a large extent and more specifically may cover a space in the shape of a hemisphere, which in turn creates conditions for ionization of the fluid passing the first arc structure to a large extent. The first independent semi arc structure created may comprise a specific type of arcs, that may be called “Ario-arcs” or “Aho discharge” (Arc- Rotary-lonization-Orbitals), having certain characteristics, such as a plurality of arcs, permanency of the arcs and stability of the arcs. In other words, the first arc structure may be configured to cover a substantial part of the container in a cross section so that when a stream of atoms/molecules in the fluid flow is conveyed past the electrodes, it makes it difficult for the atoms to pass without getting ionized.

According to one example, the discharges from the electrodes form “half-arcs” extending from each one of the electrodes to less than or about half-way into the container with regard to a central axis of the container affecting substances passing through the space between the two electrodes.

According to a further example, at least one arc at a time in the first independent semi arc structure is permanent and continuous.

According to one example, the first independent semi arc structure comprises an arc having a zigzag shape in the form of saw teeth due to the electrons push each other away due to the same electric charge. In the tips of the saw shaped arc parts, the ionization energy availability is higher (ionization happens relatively easier there) because the electrons are more excited there.

The wording “emit” electrons from the electrodes may alternatively be termed “discharge” electrons.

The method may be used for production of ROS (reactive oxygen species) and some other substances. The fluid used may here be air. After ionization, the fluid comprises a mixture of ROS (reactive oxygen species), such as Oxygen (02), Superoxide anion (02-), Peroxide (02-2), Hydrogen Peroxide (H2O2), Hydroxyl radical (OH) and Hydroxyl ion (0H-). This is a homogenous mixture of the ROS, and the mixture is substantially stable and radicals that have a relatively higher half-life It may be maintained stable to be used in a downstream application, such as a tank for cleaning of an industrial process fluid. According to one example, the process fluid is a cutting fluid resulting from an industrial cutting operation.

According to one example, the method comprises the step of supplying a magnitude of the voltage to the first pair of electrodes that selective ionization is achieved. For example, Oxygen ionizes at a lower energy than Nitrogen. More specifically, an ionization energy of about 1400 kJ/mol would ionize Oxygen and not Nitrogen. The ionization energy is carefully controlled for a specific application for preferably ionizing all the elements to Oxygen and not Nitrogen and more atomic numbers, to avoid producing NOx (NO3 - HNO3) and subsequently odour. The voltage range supplied to the electrodes is chosen in a way that the available energy for the ionization of the gaseous elements is high enough to ionize oxygen but not high enough to ionize the Nitrogen.

Even in a long-term use of the device and depreciation of the power source (such as transformer), even if the desired oxidant(s) may not be produced, but no undesired byproducts are produced, because the power would still end up below the first ionization energy of Nitrogen, and therefore, the undesired by-products are still avoided. This is one benefit of this art and is what distinguishes it from many prior arts ranging from UV and Ozone generators, which ionize Nitrogen (first ionization) and Oxygen (second ionization) and therefore produce the mentioned undesired by-products. For example, as the UV lamp depreciates, the wavelength of the emitted electromagnetic wave alters and that alteration, affect the availability of the ionization energy.

According to one example, the electrodes in the first pair of electrodes are straight and of a rod-type with a pointy end (like a needle) and arranged in-line with each other.

According to one embodiment example, the method comprises the step of supplying such a magnitude of the voltage to the electrodes that the first independent semi arc structure comprises a plurality of arcs extending from each one of the electrodes.

According to one example, there are simultaneously several streams of electrons flowing from each one of the electrodes in different paths, which form different arcs.

According to a further embodiment example, the method comprises the step of conveying the fluid past the first pair of electrodes with a fluid flow rate of such a magnitude that a first set of arcs in the first independent semi arc structure is deflected downstream from the electrodes in a direction of the fluid flow.

According to one example, the magnitude of the voltage and the fluid flow rate are matched so that at least one semi-arc in the first arc structure is permanent/continuous. The flow direction also affects bending of the semi arcs in a downstream direction. According to a further embodiment example, the container is elongated and an inner surface of the wall of the elongated fluid container has a circular shape in a cross section transverse to the longitudinal direction of the elongated fluid container, wherein the electrodes in the first pair of electrodes are arranged at a distance from each other in a transverse direction of the elongated fluid container and wherein the inner wall of the elongated fluid container has a diameter in a range of 10-50 mm, especially in the range of 10-30 mm and preferably in the range of 15-25 mm.

According to a further embodiment example, the electrodes in the first pair of electrodes are arranged at a distance from each other in a range of 2-15 mm, especially in a range of 2-10 mm and preferably in a range of 2-4 mm.

According to one example, for a container with a diameter in the range 15-25 mm, the distance between the electrodes is in the range of 2-4 mm. In this way, corrosion is minimized and the lifespan of the device is thereby increased and/or it may be more cost- effective in use in low maintenance by substituting the electrodes with the new ones less frequently. According to an alternative or complement, the electrodes are provided with chemical coatings with materials such as nano-Titanium dioxide or nano-platinum or any other material that increases the corrosion resistance of the electrodes.

According to a further embodiment example, each one of the electrodes in the first pair has an elongated shape with a pointy end and wherein the electrodes are arranged so that the pointy ends face each other. According to one example, the electrodes in the first pair of electrodes are arranged so that their longitudinal directions are in parallel with each other and preferably in-line with each other.

According to a further embodiment example, each one of the electrodes in the first pair has an elongated shape with a pointy end defining an angle in a range of 20-35°. Such sharp tips of the electrodes creates conditions for creating several paths of electrons emitted from the angled surface of the electrode at longitudinally spaced locations. According to one example, the electrodes in the first pair of electrodes are identical.

According to a further embodiment example, the method comprises the step of supplying such a voltage to the first pair of electrodes that both electrodes have either positive or negative charge simultaneously. Consequently, at a certain point in time, both electrodes in the first pair of electrodes are positively charged and therefore emit electrons, wherein the fluid flow in the environment of the respective electrode may be regarded to form a negatively charged region for interaction with the emitted electrons from the electrodes so that a first arc structure is created projecting from each one of the electrodes for ionization of the fluid.

According to a further embodiment example, the method comprises the step of supplying the voltage to each electrode in the first pair of electrodes in a range of 2-15 kV, especially in a range of 5-10 kV and preferably around 7,5 kV. It has turned out that a maximum energy level of about 1500 kJ/mol may be achieved with 7.5 kV per electrode for enabling the selective ionization as defined above.

According to one example, a transformer is connected with one of its output terminals to a first electrode in the first pair (and possibly with another one of its terminals to a first electrode in the second pair) for supplying the voltage. According to one example, AC power from a power source, such as the grid, goes to the transformer. Then the transformer turns the voltage from an input of 12 to 220 volts) with a frequency of 50 to 60 Hz to 2*7.5 kV for each pole (associated to one of the electrodes) with a frequency of about 20 kHz by changing the electric charge of the electrodes (AC current).

According to one example, supplying power to the electrodes with high frequency and high voltage creates conditions for causing a permanent and continuous arc which is strong enough not to be adversely affected by the passing fluid flow (up to 80 litres per minute). The higher frequency (of transformer) from 10, the greater number of arcs are shaped and seen.

According to a further embodiment example, the method comprises the step of supplying the fluid flow to the container with a fluid flow rate in a range of 5-80 litre/m in , especially 5- 40 litre/min and preferably 8-20 litre/min. It creates conditions for an arc structure that has the following features: a high number of semi arcs, high geographical/spatial coverage of semi arcs in the vicinity of each electrode environment per cross section of the container and an increase in ionization probability (exposure of fluid to semi arc) and ionization efficiency as a result. According to a further example, the method comprises the step of supplying the fluid flow in a pulsed manner to the inlet of the container via a pulsing duration in a range of 0,25- 3,0 seconds with a pause between consecutive pulses of 0,25-10,0 seconds and especially with a duration in a range of 0,4-1 ,0 seconds with a pause between consecutive pulses of 0, 5-5,0 seconds.

One effect of the pulsing is that there will be pressure fluctuations inside the container that leads to a “hammer-drill-effect”, wherein a distance between the molecules is decreased (and thereby a higher likelihood of ionization). Further, the pulsing affects the arcs to greater thickness compared to as if there were no pulsing. Thus, the pulsing creates conditions for a higher ionization efficiency.

A further effect of the pulsing is that for generating the same yield of oxidants, a lower volume of air is required as feed to the container, which provides for cost efficiency.

According to a further embodiment example, the method comprises the step of conveying at least a first portion of the fluid along a helical path inside of the container.

Such a fluid flow pattern allows the fluid to spend more time in the container, which creates conditions for increasing the combination rate and the likelihood of collisions and therefore ionization rate which leads to a higher ionization efficiency. Further, such a flow pattern may cause the fluid flow to arrive at the first arc structure with a direction angled in relation to a longitudinal direction of the container which in turn may cause more molecules to be ionized by the first arc structure. Further, such a flow pattern may cause turbulence in the fluid flow, which in turn may cause more molecules to be ionized by the first arc structure.

According to a further embodiment example, the method comprises the step of conveying at least a second portion of the fluid along a substantially straight path inside of the container towards a position between the first pair of electrodes. The second portion of the fluid may in this way contribute substantially to push the first independent semi arc structure downstream and thereby create conditions for a high coverage of the cross section of the container and thereby a high ionization efficiency.

According to a further embodiment example, the method comprises the step of affecting the fluid flow by a magnetic field in the vicinity of the electrodes in the first pair of electrodes for interaction with the discharged electrons from the electrodes for affecting the first arc structure for supporting the ionization of the fluid. According to one example, the method comprises the step of affecting the fluid flow by a magnetic field in the vicinity of the electrodes in the first pair of electrodes and upstream of the electrodes for interaction with the discharged electrons from the electrodes so that a second set of independent semi arcs in the first arc structure is created projecting from each one of the electrodes for supporting the ionization of the fluid, wherein the second set of arcs is created upstream of the first set of arcs in the fluid flow direction.

In other words, magnetic bridges (paths made by the magnets for the electrons) may be created in the container in the vicinity of the first pair of electrodes. The magnetic field has an effect on the electrons in the fluid flow passing by so that the electrons are maintained for a few more split seconds in the ionization area. This provides better paths for the creation of a greater number of arcs the first arc structure. Further, by applying a magnetic field a similar yield may be achieved with lower power consumption.

Arranging the magnetic field in a proper way creates conditions for creation of a plurality of the semi-arcs spreading and increasing the coverage of the cross section of the container increasing the probability of effective ionization of the conveyed fluid depending on the flow rate of the fluid and the cross section area of the container.

The term “semi arc” structure may be regarded as an arc structure between the prior art arc structures of Glow corona and streamer corona. However, since the semi arc structure introduced by this art does not have a ground pole and/or dielectric, it does not fall within the category of corona discharge and therefore it has a specific shape by a specific arrangement of magnetic field (but according to the vision error it may look like a complete arc extending between the electrodes).

According to a further embodiment example, the method comprises the step of providing a pressure in the container above 1 ,1 bars during the supply of voltage to the electrodes. According to a preferred example, the method comprises the step of providing a pressure in the container above 1 ,5 bars during the supply of voltage to the electrodes. According to one example, the method is operated with a pressure in the container in a range of 1 ,5- 2,0 bar. A pressure level above 1 ,1 bars increases the likelihood of more collisions of matter and therefore a higher ionization efficiency. The pressure required in the container is further dependent on a downstream application, wherein the pressure level may be up to 10 bars.

Accordingly, the pressure in the container is greater than the atmospheric pressure during the charging of the electrodes, wherein an increased constant pressure in a given volume in the vicinity of each electrode leads to higher chance of collision (of molecules, ions, atoms, electrons and positrons) and ionization around the respective electrode.

According to a further embodiment example, the method comprises the step of radiating the fluid in the container via a light source. The light-matter interaction provides for the phenomenon of Pair Production. In the area in which the arcs are formed, the interaction between the photons from the light source with the substances passing by the area, leads to emission of waves with different ranges of wavelength depending on the light source. The generated waves enhance the ionization efficiency. Additionally, electrons and positrons are released, and they contribute to the ionization reactions. And the yield per power consumption is increased.

The light source is preferably arranged outside of the container. It creates conditions for a long life of the light source since it will not be subjected to the interior environment (friction and heat) of the container. The radiation by the light source may radiate the fluid flow provided the container wall is transparent, such as made of glass.

The light source may be light-emitting diodes (LED) adapted for radiating an ultraviolet (UV) light. According to an alternative, a Xenon lamp may be used. According to one example, the light sources may be adapted to provide a light intensity in a range of 100- 5600 Lumen. The light intensity may be matched to the magnitude of the voltage supplied to the electrodes, wherein a lower voltage may be compensated by a higher light intensity for a certain ionization effect.

The light source may contribute to a significantly increased ionization efficiency. Tests have shown results of an increased ionization efficiency of up to 40%.

According to a further example, the ionization device comprises a second pair of electrodes arranged in the container at a distance from the first pair of electrodes. According to one example the distance between the adjacent electrode pairs is at least 30 mm.

According to a further embodiment example, a second pair of electrodes are arranged in the container opposite each other and at a distance from each other, wherein the second pair of electrodes are arranged at a distance from the first pair of electrodes downstream of the first pair in a fluid flow direction in the container, wherein the method comprises the step of charging each one of the electrodes in the second pair of electrodes so that they are simultaneously positively charged or negatively charged and synchronizing the charging of the first pair of electrodes in relation to the second pair of electrodes so that the second pair of electrodes are negatively charged when the first pair of electrodes are positively charged and vice versa.

More specifically, the second pair of electrodes are arranged at such a distance from the first pair of electrodes sufficient to avoid interference of arc structures of adjacent electrode pairs in the frequency synchronization. Further, the distance is preferably sufficient for to avoiding any direct complete arc between two electrodes of opposite charge to avoid any increase in amper load.

According to a further development of the last-mentioned embodiment example, the method comprises the step of connecting a first electrode in the first pair of electrodes and a first electrode in the second pair of electrodes to opposite terminals of a first power supply and connecting a second electrode in the first pair of electrodes and a second electrode in the second pair of electrodes to opposite terminals of a second power supply.

According to a further aspect of the invention, it regards a device for ionization of a fluid. More specifically, the device comprises a container, a first pair of electrodes arranged in the container opposite each other and at a distance from each other and a power supply adapted to charge the first pair of electrodes so that they are simultaneously positively charged or negatively charged for creating such a potential difference between each one of the electrodes and an environment of the respective electrode that electric discharges takes place from each one of the electrodes, wherein the container is adapted for conveying the fluid in a gaseous state in a flow past the first pair of electrodes in the environment of the respective electrode during said charging for ionization of the fluid. According to a further embodiment example the device comprises a second pair of electrodes arranged in the container opposite each other and at a distance from each other, wherein the second pair of electrodes are arranged at a distance from the first pair of electrodes downstream of the first pair in a fluid flow direction in the container, wherein the power supply is adapted to charge each one of the electrodes in the second pair of electrodes so that they have the same charge at the same time and to synchronize the charging of the first pair of electrodes in relation to the second pair of electrodes so that the second pair of electrodes are negatively charged when the first pair of electrodes are positively charged and vice versa.

According to a further embodiment example a first electrode in the first pair of electrodes and a first electrode in the second pair of electrodes are connected to opposite terminals of a first power supply and wherein a second electrode in the first pair of electrodes and a second electrode in the second pair of electrodes are connected to opposite terminals of a second power supply.

Further advantages and advantageous features of the invention are disclosed in the following description and in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples.

In the drawings:

Fig. 1 is a schematic view of a device for ionization of a fluid according to a first embodiment, wherein a container is shown in a cross section, Fig. 2 is a perspective view of a container in fig. 1 ,

Fig. 3 is an enlarged view of a first pair of electrodes in fig. 1 ,

Fig. 4 is a schematic top view of a first arc structure created in the container according to fig. 1 and 2 by the first pair of electrodes,

Fig. 5 is a schematic front view of the first arc structure created in the container according to fig. 1 and 2 by the first pair of electrodes,

Fig. 6 is a schematic view of a device for ionization of a fluid according to a second embodiment, wherein a container is shown in a cross section,

Fig. 7 is a perspective view of a fluid flow directing unit provided in the container in fig. 6, Fig. 8 is a front view of the fluid flow directing unit in fig. 7,

Fig. 9 is a schematic view of a device for ionization of a fluid according to a third embodiment, wherein a container is shown in a cross section,

Fig. 10 is a cross section view of the container as in fig. 9 indicating the fluid flow,

Fig. 11 is a perspective view of a device for ionization of a fluid according to a fourth embodiment,

Fig. 12 is a perspective view of a section of a magnetic field generating arrangement provided around the container in fig. 11 ,

Fig. 13 is a schematic and partly cut front view of the magnetic field generating arrangement in fig. 11 ,

Fig. 14 is a schematic top view of arc structures created in the container according to fig. 11 by the first pair of electrodes,

Fig. 15 is a schematic front view of the arc structures created in the container according to fig. 11 by the first pair of electrodes,

Fig. 16 is a schematic view in cross section of the container in fig. 11 showing parts of the magnetic field generated by the magnetic field generating arrangement,

Fig. 17 is a perspective view of a container according to an alternative design relative to the container in fig. 2,

Fig. 18 is a schematic view of the container as in fig. 17 in cross section applied in an ionization device according to a fifth embodiment indicating the fluid flow in operation, Fig. 19 is a perspective and schematic view of a device for ionization of a fluid according to a sixth embodiment,

Fig. 20 is a perspective view of a device for ionization of a fluid according to a seventh embodiment,

Fig. 21 is a graph indicating an example of a pulsed flow supplied to the ionization device, Fig. 22 is a partly cut and exploded perspective view of an arrangement for ionization of a fluid, and

Fig 23 is a schematic view of a device for ionization of a fluid according to an alternative to the first embodiment.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Fig. 1 is a schematic view of a device 2 for ionization of a fluid in a gaseous state according to a first embodiment. The fluid in gaseous state will in the following be referred to as a gas. According to one example, the gas is air. The ionization device 2 comprises a container 4. The container 4 is illustrated in a cross section in a horizontal plane through its centre axis. The container 4 has an elongated shape. The container 4 has a rounded cross section shape and more specifically a circular cross section shape. Further, the cross section of the container 4 is constant along a significant portion of the length of the container. Further, ends 6, 8 of the container 4 in the longitudinal direction have a rounded and more specifically half-spherical shape. A wall 10 of the container 4 defines an inner chamber 12. An inner surface of the wall 10 of the elongated container 4 has a diameter of about 20 mm. Fig. 2 is a perspective view from above of the container 4 in fig. 1.

The container wall 10 is formed in glass. The container may be formed in two identical container parts with a delimitation in a plane through a center axis of the container 4. According to an alternative, the container 4 is formed in one-piece with a cap at one end.

Further, an inlet 14 is provided at a first end 6 of the container 4 in its longitudinal direction and an outlet 16 is provided at a second end 8 of the container 4 in its longitudinal direction for conveying a gas flow from the inlet 14 to the outlet 16. Each one of the inlet 14 and the outlet 16 has a generally tube shape. An axis of the inlet 14 has a main direction in parallel with the longitudinal direction of the container 4 and is arranged in-line with a longitudinal centre axis 17 of the container. Likewise, an axis of the outlet 16 has a main direction in parallel with the longitudinal direction of the container 4 and is arranged in-line with the longitudinal centre axis 17 of the container. The container 4 has a length in a range of 100 - 120 mm excluding the inlet 14 and outlet 16.

The ionization device 2 further comprises a first pair 18 of electrodes 20, 22 arranged in the container 4 opposite each other and at a distance from each other. The electrodes 20, 22 are arranged perpendicularly relative to the longitudinal direction of the container 4. Further, the container 4 is arranged in a way that its longitudinal direction is in a horizontal plane. More specifically, the electrodes 20, 22 are arranged so that they extend in a horizontal plane. The electrodes 20, 22 are shown in an enlarged view in figure 3. The electrodes 20, 22 are arranged at a distance y from each other in a range of 2-4 mm. Further, each one of the electrodes 20, 22 in the first pair 18 has an elongated shape with a circular cross section and a pointy end 24, 26. The electrodes are arranged so that the pointy ends 24, 26 face each other. More specifically, each one of the electrodes 20, 22 in the first pair 18 has an elongated shape with a pointy end 24, 26 defining an angle a in a range of 20-35°. In other words, each one of the electrodes 20, 22 has a sharp tip. More specifically, the electrodes 20, 22 in the first pair 18 are straight and arranged in-line with each other. More specifically, the electrodes 20, 22 in the first pair 18 are in the form of rods. The electrodes 20, 22 in the first pair 18 may be termed needle electrodes. The electrodes 20, 22 in the first pair 18 are formed in a metallic material and more precisely in the material tungsten (also called wolfram) as an example.

According to physics law, when charging an element, the charged parts accumulate in any sharp edges of the element. Accordingly, charged parts will be highly accumulated in the sharp edge of the electrode 20, 22. In other words, charged parts will have a very high density in the sharp edge, wherein an electric field will be strong in a region of the sharp edge. Further, a highly charged electrode (positive or negative) will have a very high potential in relation to the environment (adjacent the electrode). The potential difference between the electrode and its adjacent environment/surroundings will result in ionization of the matter in the environment in the vicinity of the respective electrode leading to exchange of electrons/positrons in cycles from higher potential area to lower potential area and vice versa and different types of electric discharge from the electrode may take place. This phenomenon may be similar to a Tesla coil.

Accordingly, the design of the electrodes 20, 22 with sharp tips especially with an acute angle from 20 to 35 degrees (preferably 22 degrees to create a greater number of semi arcs as well as increasing the life span of the electrodes) 24, 26 creates good conditions for creating electric discharges in the form of electric semi-arcs from the surface of the tip having an inclination relative to the longitudinal direction of the elongate electrode. More specifically, a first set of arcs may be created extending from the electrode tip in a downstream direction. Further, a second set of arcs may be created extending from the electrode tip in an upstream direction. It will be described in more detail below in association with fig. 14 and fig. 15.

The ionization device 2 further comprises a power supply 28, 50 adapted for charging each one of the electrodes 20, 22 in the first pair 18 of electrodes so that they have the same charge simultaneously. In this way, such a potential difference between each one of the electrodes 20, 22 and an environment of the respective electrode may be created that electric discharges take place simultaneously from each one of the electrodes. Further, the fluid is conveyed in a gaseous state inside the container past the first pair 18 of electrodes in the environment of the respective electrode 20, 22 during said charging for ionization of the fluid.

More specifically, the power supply 28, 50 comprises two transformers 28, 50, which are adapted to provide an alternating current of a certain frequency to the electrodes. Accordingly, the power supply 28, 50 is adapted to supply such a voltage to the first pair 18 of electrodes that both electrodes 20, 22 are positively charged at the same time and therefore emit electrons. It is schematically shown in a top view in figure 4, wherein the arrows 30, 31 indicate paths of electrons emitted from the tips of the electrodes 20, 22. Further, the container 4 is adapted for conveying the gas in a flow past the first pair 18 of electrodes, wherein the gas flow may be regarded as a negatively charged region 32 between the electrodes 20, 22 for interaction with the emitted electrons from the electrodes so that a first arc structure 34 may be created. More specifically, a plurality of electric semi-arcs project from each one of the electrodes 20, 22 for ionization of the gas. Fig. 5 is a schematic front view of the first arc structure 34 created in the container according to fig. 4. Further, each arc has a zigzag shape in the form of saw teeth.

More specifically, each transformer 28, 50 comprises a primary winding and a secondary winding. Each transformer turns the voltage from an input of 12 to 220 volts with a frequency of 50 to 60 Hz to 2*7.5 kV for each pole (associated to one of the electrodes) with a frequency of about 20 kHz by changing the electric charge of the electrodes (AC current). Accordingly, each transformer 28, 50 comprises a frequency converter 29, 51 where one of the ground wire functions is to reduce noise.

It should be noted that the zigzag arc shapes shown in the fig. 4 and fig. 5 are only schematically shown. Especially, the semi-arcs are magnified and much bigger than the real size in relation to the size of the electrodes 20, 22. In reality the zigzags are in microscopic scales. Also, their plurality is much higher than the number of the arcs shown in the figures.

Each one of the transformers 28, 50 is adapted for supplying an output voltage at a magnitude of around 7,5 kV via each one of its output terminals. Further, each one of the transformers 28, 50 is adapted for supplying the output voltage in a frequency about 20 kHz, wherein the polarity of the electrodes connected to the two output terminals/poles of one transformer will change very fast (every 0.00005 second). More specifically, each one of the electrodes 20, 22 is arranged in an opening 36, 38 through the container wall 10. More specifically, the container comprises a pipe-shaped portion 40, 42 extending in a transverse direction relative to the longitudinal direction of the container 4. More specifically, the pipe-shaped portion 40, 42 extends perpendicularly relative to the longitudinal direction of the container 4. The pipe-shaped portions 40, 42 define the openings 36, 38. More specifically, the pipe-shaped portions 40, 42 are formed in one-piece with the container 4. More specifically, the electrodes 20, 22 are arranged in the pipe-shaped portions 40, 42 in a gas tight manner for avoiding leakage.

The ionization device 2 further comprises a second pair 44 of electrodes 46, 48 arranged in the container 4 in a similar way as has been described above with regard to the first pair 18 of electrodes 20, 22. The second pair 44 of electrodes 46, 48 are arranged at a distance from the first pair 18 of electrodes 20, 22 in the longitudinal direction of the container 4. Each one of the first pair 18 of electrodes 20, 22 and the second pair 44 of electrodes 46, 48 are arranged at the portion of the container 4 having a constant cross section with a distance between the adjacent electrode pairs of about 30 mm. The power supply 28,50 is adapted for charging each one of the electrodes 46, 48 in the second pair 44 of electrodes so that they have the same charge at the same time. In this way, such a potential difference between each one of the electrodes 46, 48 and an environment of the respective electrode may be created that electric discharges take place from each one of the electrodes separately. Accordingly, the power supply 28, 50 is adapted to supply such a voltage also to the second pair 44 of electrodes that both electrodes 46, 48 are positively charged at the same time and therefore emit/exchange electrons/positrons.

The arrangement is adapted to synchronize the charging of the first pair 20 of electrodes 20, 22 in relation to the second pair 44 of electrodes 46, 48 so that the second pair 44 of electrodes 46, 48 are negatively charged when the first pair 20 of electrodes 20, 22 are positively charged and vice versa.

The two transformers 28, 50 are of the same natural frequency and identical. By arranging the transformers 28, 50 adjacent each other in relative close proximity, their frequency cycles will become synced eventually in a steady state since they would influence each other during operation, due to Hertz and frequency laws. Accordingly, they can work with a synced frequency permanently. Accordingly, this synchronization happens spontaneously as soon as the transformers are turned on. According to an alternative, means may be provided to actively control the synchronization, such as arranging a oneway diode (a diode that synchronize the direction of the current in the same direction - the sinus or cosinus wave) in the path of each exit terminal.

Accordingly, each one of the transformers has two output terminals/poles, which are connected to the electrodes 20, 22; 46, 48 for charging the electrodes. When the potential reaches an amount that is sufficient for electric discharge, the above-mentioned phenomenon of electric discharge will take place. More specifically, a first electrode 22 in the first pair 18 of electrodes and a first electrode 46 in the second pair 44 of electrodes are connected to opposite terminals of a first transformer 28. Further, a second electrode 20 in the first pair 18 of electrodes and a second electrode 48 in the second pair 44 of electrodes are connected to opposite terminals of a second transformer 50.

The ionization device 2 further comprises a gas flow pumping means 52 for supplying the gas flow from a tank 54 of compressed air to the inlet 14 of the container 4. More specifically, the gas flow pumping means 52 is adapted for supplying the gas flow at such a rate to the container 4 that it is conveyed past the first pair 18 of electrodes 20, 22 so that at least parts of the first arc structure are deflected downstream from the electrodes 20, 22 in a direction of the gas flow. More specifically, the gas flow pumping means 52 is adapted for supplying the gas flow to the container with a gas flow rate in a range of 10-12 litre/min.

It may be noted that the device is not limited to an application of a tank for supply of the gas. It can be a compressor using ambient air or an industrial blower, etc.

Further, the gas flow pumping means 52 is adapted for supplying the gas flow to the inlet 14 of the container 4 in a pulsed manner. The method comprises the step of supplying the gas flow in a pulsed manner to the inlet 14 of the container 4 via a pulsing duration at about 0,5 seconds with a pause between consecutive pulses of about 1 ,5 seconds, see graph in fig. 21 .

The outlet 16 of the container 4 is in fluid communication with a tank 56 comprising a process liquid, such as industrial water or wastewater that have strong aerobic or anaerobic bacteria. A line connecting the outlet 16 with the tank 56 ends in a lower region of the tank 56 so that the ionized gas may be supplied below a surface of the process liquid in order to separate inorganic or mineral substances such as metal by sedimentation or kill the bacteria.

According to an alternative, the tank 56 is replaced with another device that relates to air purification. The ionized gas exiting the outlet can be directly sprayed to a room to eliminate virus, bacteria, odour, etc.

A further effect of the pulsing is that a less amount of unionized air (02) per volume of output is sent to the tank 56. Unionized air may risk support the aerobic bacteria to grow and it will compete with the ionized portion of the air. With pulsing, more ionized air compared to unprocessed air (02) is sent in the mixture per volume of output fluid.

Fig. 6 is a schematic view of a device 102 for ionization of a gas according to a second embodiment. The ionization device 102 according to the second embodiment has many parts in common with the ionization device 2 according to the first embodiment. For ease of presentation, only the main differences will be explained below.

The ionization device 102 comprises a nozzle 104 arranged in the inlet 14 of the container 4. The nozzle 4 is adapted for being rotated around an axis in parallel with an axis of the inlet 14 for conveying the gas along a helical path inside of the container 4. The nozzle 104 comprises an end portion facing the container inner chamber 12 having radially external surfaces defining a generally circular cross section shape that is matched to a dimension of an inner surface of the inlet 14. Further, the nozzle 104 comprises peripheral through-going channels adapted for creating a helical flow inside of the container 4.

The ionization device 102 further comprises a first fluid flow directing unit 106 arranged in the container 4. The first fluid flow directing unit 106 is arranged downstream of the first pair 18 of electrodes. More specifically, the first fluid flow directing unit 106 is arranged downstream of the second pair 44 of electrodes.

The first fluid flow directing unit 106 is adapted to compensate for a pressure drop throughout the length of the container 4 by providing a hindrance to the gas flow. In this way, a second arc structure created by the second pair 44 of electrodes may be as strong and disciplined as the first arc structure created by the first pair 18 of electrodes. More specifically, the pressure in the container 4 is maintained or at least not significantly reduced thanks to the first fluid flow directing unit 106. A distance between the molecules is decreased and the retention time in the container is increased and consequently the ionization efficiency increases. Further, maintaining the pressure at a relatively high level may be important for the delivery of the fluid to the tank 56, since the liquid in the tank provides a counterpressure that needs to be overcome.

Fig. 7 is a perspective view of the first fluid flow directing unit 106 provided in the container 4 in fig. 6. Fig. 8 is a front view of the first fluid flow directing unit 106 in fig. 7. The first fluid flow directing unit 106 comprises at least one peripheral fluid flow guide channel 108 having an outlet 110 circumferentially displaced relative to an inlet 112 for turning a first part of an incoming fluid flow. The first fluid flow directing unit 106 further comprises a central fluid flow guide channel 114 with an extension substantially in parallel with the longitudinal direction of the elongated container 4 for guiding a second part of the incoming fluid flow substantially in the longitudinal direction of the elongated container 4.

More specifically, the first fluid flow directing unit 106 comprises a plurality of circumferentially spaced peripheral fluid flow guide channels 108, 118, 120. Further, the at least one peripheral fluid flow guide channel 108, 118, 120 has a substantially larger dimension than the central fluid flow guide channel 114 for conveying a substantially larger part of the incoming fluid flow.

Further, the first fluid flow directing unit 106 has a rounded peripheral surface 122 substantially corresponding to a curvature of the rounded inner surface of the container 4, wherein the first fluid flow directing unit 106 is arranged in the container 4 so that the rounded surfaces are in contact with each other in a fluid tight manner.

More specifically, the first fluid flow directing unit 106 is rigidly connected, such as via weld seams, to the container 4 in an operational position. The first fluid flow directing unit 106 may be formed in a material with the same or similar expansion coefficient as the container wall 10. According to one example, the first fluid flow directing unit 106 is formed in glass. It creates conditions for rigidly connecting the first fluid flow directing unit 106 to the container 4 in the operational position via welding.

More specifically, the first fluid flow directing unit 106 comprises a body 124 defining the at least one peripheral fluid flow guide channel 108, 118, 120 and the central fluid flow guide channel 114. More specifically, the first fluid flow directing unit 106 is formed by a one-piece body 124.

The at least one peripheral fluid flow guide channel 108, 118, 120 is open in a radial direction of the first fluid flow directing unit 106. More specifically, at least one peripheral fluid flow guide channel 108, 118, 120 is closed in the radial direction by the wall 10 of the container 4 in figure 6.

The first fluid flow directing unit 106 comprises sections 126, 128, 130 circumferentially between adjacent peripheral fluid flow guide channels 108, 118, 120. A radially outer surface of these sections 126, 128, 130 of the first fluid flow directing unit 106 defines a circular shape of substantially the same dimension as the inner surface of the elongated container 4. A wall of each one of the sections 126, 128, 130 faces in the longitudinal direction of the container 4 for blocking parts of the fluid flow. A total area of the walls of the sections 126, 128, 130 is substantially the same as a cross section area defined by the peripheral fluid flow guide channels 108, 118, 120.

The first fluid flow directing unit 106 is adapted for conveying at least a first portion of the fluid along a helical path inside of the container 4 via the at least one peripheral fluid flow guide channel 108, 118, 120. Further, the first fluid flow directing unit 106 is adapted for conveying at least a second portion of the fluid along a substantially straight path inside of the container via the central fluid flow guide channel 114.

Fig. 9 is a perspective view of a device 202 for ionization of a gas according to a third embodiment. The ionization device 202 according to the third embodiment has many parts in common with the ionization device 102 according to the second embodiment. For ease of presentation, only the main differences will be explained below.

The ionization device 202 comprises a second fluid flow directing unit 206. The two fluid flow directing units 106, 206 are arranged spaced from each other in the longitudinal direction of the container 4. More specifically, the two fluid flow directing units 106, 206 are arranged on opposite sides of the first pair 18 of electrodes 20, 22. More specifically, the two fluid flow directing units 106, 206 are arranged on opposite sides of the first pair 18 of electrodes 20, 22 and the second pair 44 of electrodes 46, 48. More specifically, the second fluid flow directing unit 206 has a design similar to the design of the first fluid flow directing unit 106 with the difference that the at least one peripheral fluid flow guide channel is turned circumferentially in an opposite direction. Thus, the two fluid flow directing units 106, 206 are identical in dimension but have a mirrored design for the change of direction of the fluid flow. In other words, a first one of the two fluid flow directing units 106, 206 is adapted to turn the fluid flow in a clockwise direction and the other one is adapted to turn the fluid flow in a counterclockwise direction.

Fig. 10 is a schematic top view of the ionization device 202 as in fig. 9 indicating the fluid flow paths. The peripheral fluid flow guide channel 108, 118, 120 of the upstream first fluid flow directing unit 206 are adapted to convey a first part of the fluid flow in a helical path 208 inside the container 4. Further, the central fluid flow guide channel 114 is adapted to convey a second part of the fluid flow in a substantially straight path 210 inside of the container in parallel with the longitudinal direction of the container 4.

Fig. 11 is a perspective view of parts of a device 302 for ionization of a gas according to a fourth embodiment. The ionization device 302 according to the fourth embodiment has many parts in common with the ionization device 202 according to the third embodiment. For ease of presentation, only the main differences will be explained below.

The ionization device 302 comprises a magnetic field generating arrangement 304, which is adapted for generating a magnetic field in the vicinity of the first pair 18 of electrodes for affecting the arc structures for supporting the ionization of the gas. The magnetic field generating arrangement 304 is arranged outside of the container 4. It creates conditions for a long life of the magnetic field generating arrangement 304 since it will not be subjected to the interior environment (friction and heat) of the container 4.

The magnetic field generating arrangement 304 comprises a first section 305 arranged upstream of the first pair 18 of electrodes in the longitudinal direction of the container, wherein the first arc structure 34 comprises a first set of arcs 334 that are deflected downstream from the electrodes by the gas flow and a second set of arcs 336 extending upstream from the electrodes 20, 22 by the effect of the magnetic field of the first magnetic field generating section 305. The first set of arcs 334 and the second set of arcs 336 are shown in fig. 14 and fig. 15. It may be noted that the second set of arcs 336 comprises fewer arcs than the first set of arcs 334 and that the arcs in the second set of arcs 336 have a smaller extension in the longitudinal direction of the container relative to the first set of arcs 334.

More specifically, the magnetic field generated by the first magnetic field generating section 305 creates bridges/pathways for arcs also upstream of the electrode pair 18, see arrows 330 and 331 indicating the electrons emitted from the electrodes 20, 22. The second set of arcs 336 comprises a plurality of arcs projecting from each one of the electrodes 20, 22. Further, the magnetic field generated by the first magnetic field generating section 305 is adapted for deflecting the second set of arcs 336 upstream from the electrodes 20, 22 in a direction of the gas flow. Further, the arcs have a zigzag/saw- tooth shape.

The magnetic field generating arrangement 304 comprises at least one magnetic field generating unit 310. The magnetic field generating unit 310 is formed by an electromagnet 308. The electromagnet 308 comprises a coil adapted for the passage of electric current. The electromagnet 308 is arranged so that an axis of the coil extends in a radial direction in relation to the container 4. According to an alternative, the magnetic field generating unit 310 is formed by a permanent magnet. The magnetic field generating unit is adapted for providing a magnetic strength in a range of 20-180 and especially in a range of 20-40 N.

More specifically, the first magnetic field generating section 305 comprises a plurality of circumferentially spaced magnetic field generating units 310 around the container. According to the shown example, the first magnetic field generating section 305 comprises six circumferentially spaced magnetic field generating units 310 around the container. Such an arrangement provides for even more organized and symmetric arc structure spreading all around the electrode pair evenly in all direction and cover the whole cross-section of the reaction chamber, proportionately to the controlled flow rate of the conveyed fluid. The number of magnetic field generating units 310 may of course be altered depending on the application. Further, each one of the circumferentially spaced magnetic field generating units 310 is formed by an electromagnet. The magnets may be connected to a low voltage circuit, for example 12 to 24 volts. According to an alternative, one or several or all of the circumferentially spaced magnetic field generating units 310 may be formed by a permanent magnet. Referring now also to fig. 12 that is a perspective view of the first magnetic field generating section 305. The first magnetic field generating section 305 comprises a ringshaped support 312 extending around the container, wherein the ring-shaped support is adapted to hold the circumferentially spaced magnetic field generating units 310 in their operational positions. Each one of the circumferentially spaced magnetic field generating units 310 is arranged so that its axis extends radially outwards from the ring-shaped support 312.

Fig. 13 is a partly cut front view of the ionization device 302 in fig. 11. The ring-shaped support 312 is arranged in close proximity to an outer wall surface of the container 4. More specifically, the ring-shaped support 312 has an inner diameter that is substantially the same as or somewhat larger than an outer diameter of the container 4. It may be noted that the magnets are arranged so that a core of each magnet is in contact with an outer surface of the glass container. The ring-shaped support 312 is made of graphite or any non-conductive material with high thermal tolerance.

With reference to fig. 11 , the magnetic field generating arrangement 304 comprises a second section 307, which is arranged outside of the container and downstream of the first pair 18 of electrodes in the longitudinal direction of the container 4, wherein the second magnetic field generating section 307 is adapted for generating a magnetic field in the vicinity of the first pair of electrodes for stabilizing the first arc structure. More specifically, the magnetic field created by the second magnetic field generating section 307 is adapted for disciplining the first set of arcs and give them a more coherent arrangement. In other words, the disciplining of the arcs means that the arcs form a more symmetric pattern with certain spacings etc. Also, the magnetic field created by the second magnetic field generating section 307 effects the first set of arcs to increase the quantity of the arcs as well as an increased thickness of the arcs. The second magnetic field generating section 307 is similar in construction and functionality as the first magnetic field generating section 305.

Further, the magnetic field generating arrangement 304 comprises a third section 309, which is arranged outside of the container and upstream of the second pair 44 of electrodes in the longitudinal direction of the container 4. The third magnetic field generating section 309 is adapted for generating a magnetic field in the vicinity of the second pair 44 of electrodes similar to how the first magnetic field generating section 305 is adapted for generating the magnetic field in the vicinity of the first pair 18 of electrodes and will therefore not be described in any further detail here.

Fig. 16 is a schematic top view of the magnetic field generating arrangement 304 schematically showing parts 311 of the magnetic fields generated. More specifically, fig. 16 shows the magnetic fields generated by two opposite magnetic field generating units 310. Similar magnetic fields are created by each one of the other two pairs of opposite magnetic field generating units 310.

Fig. 17 is a perspective view of a container 404 according to an alternative design relative to the container 4 in fig. 2. The container 404 differs in relation to the container 4 in fig. 2 in that it has a further outlet 416. The further outlet 416 is arranged inclined in relation to the longitudinal direction of the container 404. More specifically, the further outlet 416 is arranged with an angle of its axis in relation to the axis of the outlet 16 in a range of 30- 60° and preferably about 45°. Further, the further outlet 416 is arranged extending from the half-spherical end 8 of the container 404. The arrangement of two outlets 4, 404 creates conditions for dividing the ionized gas flow into two separate gas flows to different destinations. According to one example, one of the outlets 16, 416 may be in fluid communication with the inlet 14 for recirculation of a part of the ionized fluid flow.

Fig. 18 shows an ionization device 402 according to a fifth embodiment comprising the container 404 according to fig. 17. It indicates the fluid flow paths inside of the container 404. More specifically, the design and position of the first fluid flow directing unit 106 is designed for conveying a first part of the fluid towards the axial outlet 16 and a second part of the fluid towards the further second outlet 416.

The ionization device 402 may as an alternative or complement to the first fluid flow directing unit 106 further comprise means for selective guiding of parts of the fluid flow to the outlets 16, 416. According to one example, the fluid flow selective guiding means is adapted to attract a negatively charged part of the flow to the further outlet 416. It may be formed by a further electrode acting as a cathode. Since electrons has a negative charge and some of the ionized molecules/atoms are positively charged, the cathode may attract the negatively charged part of the flow to the further outlet 416 and it can be used for another purpose (for example returning to the inlet 14 or for other purposes). In this way, the axial main output (the target ionization) in the axial outlet 16 is more purified. According to an alternative or complement, an anode may be used to absorb the positively charged part of the flow depending on the purpose.

Fig. 19 is a schematic side view of parts of an ionization device 502 according to a sixth embodiment. The ionization device 502 according to the sixth embodiment has many parts in common with the ionization device 2 according to the first embodiment. For ease of presentation, only the main differences will be explained below.

The ionization device 502 comprises at least one light source 504, 506, which is adapted to subject the gas flow in the container for radiation and thereby support the ionization of the gas. The light-matter interaction provides for the phenomenon of Pair Production.

The light source 504, 506 is in the shape of a strip extending in the longitudinal direction of the container 4. The light source 504, 506 strip has a main extension along a straight line. More specifically, two light sources 504, 506 are arranged opposite each other, ie spaced with 180°. More specifically, the two light sources 504, 506 are arranged so that their longitudinal directions are in parallel with each other. More specifically, the strip shaped light source extends along a substantial part of the container 4 and in the shown example substantially along its complete length. The light source 504, 506 is arranged outside of the container 4. It creates conditions for a long life of the light source 504 since it will not be subjected to the interior environment (friction and heat) of the container 4. The radiation by the light source 504 may radiate the fluid flow thanks to the fact that the container wall is transparent.

The at least one light source 504, 506 comprises a plurality of light source units arranged in a spaced relationship in a longitudinal direction of the respective strip. The light source 504, 506 may be light-emitting diodes (LED) adapted for radiating an ultraviolet (UV) light. According to an alternative, a Xenon lamp may be used. According to one example, the light sources 504, 506 may be adapted to provide a light intensity in a range of 100-5600 Lumen. The light intensity may be matched to the magnitude of the voltage supplied to the electrodes, wherein a lower voltage may be compensated by a higher light intensity for a certain ionization effect.

According to an alternative, the light source may be a light bulb instead of a strip. Also other shapes and arrangements of the light source may be applicable. Fig. 20 is a schematic and partly cut side view of parts of an ionization device 602 according to a seventh embodiment. The ionization device 602 according to the seventh embodiment has many parts in common with the ionization device 502 according to the sixth embodiment. For ease of presentation, only the main differences will be explained below.

The ionization device 602 comprises the magnetic field generating arrangement 304 as in fig. 11 . The ionization device 602 further comprises a support structure 604 for supporting the container 4, the light sources 504, 506 and the magnetic field generating arrangement 304 in predefined positions. More specifically, the support structure 604 comprises two blocks 606, 608. The blocks 606, 608 are adapted to be positioned on top of each other. Each block 606, 608 comprises a receptacle 610, 612 in the surfaces adapted to face each other. The receptacle 610, 612 has an elongated extension defining a half-circle in cross section for receiving the container 4. Further, each block 606, 608 is designed with internal chambers/receptacles for receiving the light sources 504, 506 and the magnetic field generating arrangement 304. Further, each block 606, 608 is provided with through holes 614 in a certain configuration for matching each other in order to receive bolts for securing the blocks 606, 608 to each other. Further, each block 606, 608 may be adapted to also receive the transformers 28, 50.

Fig. 22 is a partly cut and exploded perspective view of an arrangement 702 for ionization of a fluid. The arrangement 702 comprises the ionization device 302 in fig. 11 arranged in a casing 714 that has a generally circular cylindrical outer shape. The arrangement 702 comprises a generally flat rectangular wall 718 and wall 720 that is generally half-circular in cross section, which is connected to the flat rectangular wall 718 in a way defining an internal space between the walls 718, 720. The ionization device 302 is arranged in the internal space between the walls 718, 720. The transformers 28, 50 are arranged on either side of the container 4 in its longitudinal direction and connected to the electrodes 20, 22, 46, 48 as described above. Further, the transformers are located within the internal space between the walls 718, 720.

Fig 23 is a schematic view of a device 802 for ionization of a fluid according to an alternative to the first embodiment. The ionization device 802 differs from the first embodiment in the structure of the transformers 828, 850. More specifically, a secondary mid-point of a secondary winding is connected to earth.

It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims.

The invention has been described above for an application of cleaning industrial process liquids. According to an alternative, the invention may be used for cleaning wastewater, such as municipal wastewater. According to an alternative, the invention may be used for cleaning air, such as air in buildings. The ionized gas may be used for eliminating organic and mineral impurities or pollutants. Such organic matter may be bacteria, viruses, other harmful microorganisms, and some organic chemical substances.

Claims

1 . A method for ionization of a fluid, wherein a first pair (18) of electrodes (20, 22) are arranged in a container (4, 404) opposite each other and at a distance from each other, wherein the method comprises the step of charging each one of the electrodes (20, 22) in the first pair (18) of electrodes so that they are simultaneously negatively or positively charged creating such a potential difference between each one of the electrodes (20, 22) and an environment of the respective electrode that electric discharges takes place from each one of the electrodes, wherein the method comprises the step of conveying the fluid in a gaseous state inside the container past the first pair (18) of electrodes in the environment of the respective electrode (20, 22) during said charging for ionization of the fluid

2. A method according to claim 1 , wherein the method comprises the step of high frequency charging the electrodes (20, 22) in the first pair (18) of electrodes (20, 22) to an extent that the electric discharges comprises a plurality of independent semi arc structures formed at the same time from each one of the electrodes (20, 22).

3. A method according to claim 2, wherein the method comprises the step of conveying the fluid past the first pair of electrodes (20, 22) with a fluid flow rate of such a magnitude that the independent semi arc structures are deflected downstream from the electrodes in a direction of the fluid flow.

4. A method according to any preceding claim, wherein the container (4, 104) is elongated and an inner surface of a wall (10) of the elongated fluid container (4, 104) has a circular shape in a cross section transverse to the longitudinal direction of the elongated fluid container, wherein the electrodes (20, 22) in the first pair (18) of electrodes are arranged at a distance from each other in a transverse direction of the elongated fluid container and wherein the inner wall of the elongated fluid container has a diameter in a range of 10-50 mm, especially in the range of 10-30 mm and preferably in the range of 15-25 mm.

5. A method according to any preceding claim, wherein the electrodes (20, 22) in the first pair (18) of electrodes are arranged at a distance from each other in a range of 2-15 mm, especially in a range of 2-10 mm and preferably in a range of 2-4 mm.

6. A method according to any preceding claim, wherein each one of the electrodes (20, 22) in the first pair has an elongated shape with a pointy end and wherein the electrodes are arranged so that the pointy ends face each other.

7. A method according to claim 6, wherein each one of the electrodes (20, 22) in the first pair has an elongated shape with a pointy end defining an angle in a range of 20-35°.

8. A method according to any preceding claim, wherein the method comprises the step of supplying such a voltage to the first pair (18) of electrodes (20, 22) that both electrodes have either positive or negative charge at the same time.

9. A method according to claim 8, wherein the method comprises the step of supplying the voltage to each electrode (20, 22) in the first pair of electrodes in a range of 2 to 15 kV, especially in a range of 5 to 10 kV and preferably around 7,5 kV.

10. A method according to claim 8 or 9, wherein method comprises the step of supplying the voltage to each electrode (20, 22) in the first pair of electrodes in a frequency range of 10-30 kHz and especially about 20 kHz.

11. A method according to any preceding claim, wherein method comprises the step of supplying the fluid flow to the container (4) with a fluid flow rate in a range of 5- 80 litre/min, especially 5-40 litre/min and preferably 8-20 litre/min.

12. A method according to any preceding claim, wherein the method comprises the step of conveying at least a first portion of the fluid along a helical path inside of the container.

13. A method according to any preceding claim, wherein the method comprises the step of conveying at least a second portion of the fluid along a substantially straight path inside of the container towards a position between the first pair of electrodes. A method according to any preceding claim, wherein the method comprises the step of affecting the fluid flow by a magnetic field (311 ) in the vicinity of the electrodes (20, 22) in the first pair (18) of electrodes for affecting a structure of the electric discharges for supporting the ionization of the fluid by stabilizing and disciplining the independent semi arc structures . A method according to any preceding claim, wherein the method comprises the step of providing a pressure in the container above 1 ,1 bars during the charging of the electrodes,. A method according to any preceding claim, wherein the method comprises the step of radiating the fluid in the container via a light source (504, 506) leading to increased ionization efficiency. A method according to any preceding claim, wherein a second pair (44) of electrodes (46, 48) are arranged in the container (4, 404) opposite each other and at a distance from each other, wherein the second pair (44) of electrodes (46, 48) are arranged at a distance from the first pair (18) of electrodes (20, 22) downstream of the first pair (18) in a fluid flow direction in the container, wherein the method comprises the step of charging each one of the electrodes (46, 48) in the second pair (44) of electrodes so that they are simultaneously negatively or positively charged and synchronizing the charging of the first pair (20) of electrodes (20, 22) in relation to the second pair (44) of electrodes (46, 48) o that the second pair (44) of electrodes (46, 48) are negatively charged when the first pair (20) of electrodes (20, 22) are positively charged and vice versa. A method according to claim 17, wherein the method comprises the step of connecting a first electrode in the first pair (18) of electrodes (20, 22) and a first electrode in the second pair (44) of electrodes (46, 48) to opposite terminals of a first power supply (28) and connecting a second electrode in the first pair (18) of electrodes (20, 22) and a second electrode in the second pair (44) of electrodes (46, 48) to opposite terminals of a second power supply (50).

19. A method according to claim 18, wherein the first power supply (28) and the second power supply are formed by two identical transformers.

20. A method according to any preceding claim, wherein a magnitude of the voltage supplied to the electrodes is chosen in a way that the available energy for the ionization of the gaseous elements is high enough to ionize oxygen but not high enough to ionize the Nitrogen.

21. A device (2, 102, 202, 302, 402, 502) for ionization of a fluid, wherein the device comprises a container (4, 404), a first pair (18) of electrodes (20, 22) arranged in the container opposite each other and at a distance from each other and a power supply (28, 50) adapted to charge the first pair (18) of electrodes so that they are simultaneously negatively or positively chargedfor creating such a potential difference between each one of the electrodes (20, 22) and an environment of the respective electrode that electric discharges takes place from each one of the electrodes, wherein the container (4, 404) is adapted for conveying the fluid in a gaseous state in a flow past the first pair (18) of electrodes in the environment of the respective electrode (20, 22) during said charging for ionization of the fluid.

22. A device according to claim 21 , wherein the device comprises a second pair (44) of electrodes (46, 48) arranged in the container (4, 404) opposite each other and at a distance from each other, wherein the second pair (44) of electrodes (46, 48) are arranged at a distance from the first pair (18) of electrodes (20, 22) downstream of the first pair (18) in a fluid flow direction in the container, wherein the power supply (28, 50) is adapted to charge each one of the electrodes (46, 48) in the second pair (44) of electrodes so that they are simultaneously negatively or positively charged and to synchronize the charging of the first pair (20) of electrodes (20, 22) in relation to the second pair (44) of electrodes (46, 48) so that the second pair (44) of electrodes (46, 48) are negatively charged when the first pair (20) of electrodes (20, 22) are positively charged and vice versa.

23. A device according to claim 21 or 22, wherein a first electrode in the first pair (18) of electrodes (20, 22) and a first electrode in the second pair (44) of electrodes (46, 48) are connected to opposite terminals of a first power supply (28) and wherein a second electrode in the first pair (18) of electrodes (20, 22) and a second electrode in the second pair (44) of electrodes (46, 48) are connected to opposite terminals of a second power supply (50).